My wife, knowing how much I love techy stuff bought me the Fugi E900 9.8 megapexel digi camera. Digital Camera Magazine’s point and shoot digi of the year 06’.
This little digi is an accompanyment to the Nikon D-70 which she uses for her business and various family affairs.
My question is this - what the heck are we going to use the 9.8 megapixels for? And just how big can we blow up the images we will get from this thing? As I understand it the more megapixels one has the further one can blow the image up. Is this true? Can we truly get poster sized (24x36) images from this?
The thing with resolution (the term generally used for number of pixels) is that final picture quality doesn’t just depend on how many pixels you have, but what “type” of pixels they are. That is, what type of sensor are they on?
While your new point-and-shoot has over 50% more pixels than your D70, those pixels are arrayed on a much smaller sensor, and so each pixel on your E900 is considerably smaller than each pixel on the D70. The sensor in the E900 is a 1/1.6 sensor, meaning that it’s about 8mm wide and about 6mm high. By contrast, the DX sensor on your Nikon is 23.7mm wide and 15.7mm high.
Larger pixels on larger sensors tend to be less prone to “noise” and other problems associated with digital photography, and tend to offer better color rendition and better dynamic range. All this generally leads to higher quality images from larger sensors, even if they have fewer pixels.
Unfortunately, the marketing hype has led many people to believe that pixel count is the be-all-and-end-all of digital camera quality, when it’s really a lot more complicated than that. For example, even beyond the sensor itself, if you shoot in JPEG (instead of RAW), the camera’s compression algorithm can also have a significant effect on the quality of the final image.
None of this is to say that your new camera won’t produce great images. My four-year-old Minolta Dimage 7Hi (5MP on a small sensor) gives pretty damn good pictures, and your new Fuji will probably be considerably better than that. But, while i haven’t read any reviews of the Fuji or seen any image tests, i’d be willing to bet that your D70 will still produce enlargements that are just as good as, if not better than, the Fuji.
If you know what you’re doing or send the file to a good printer, with upsampling you can get a much, much larger print than that. I have a perfectly good-looking 13x19" print at 300 dpi from a 2.7 megapixel camera (Nikon D1) hanging in my living room.
Of course, the file has to be perfect, and the pixels have to be “good” (what got is 9.8 MP if it’s 9.8 MP of crap?) I would be hesitant to print larger than an 8" x 10" with a point-and-shoot, no matter how many pixels it produces. So, for the E900, I’d stay within these limits. With your 6 megapixel D70, I would have no reservations printing up to and beyond 13"x19", provided you use good glass and the pictures are properly exposed and everything.
It also depends on the subject and lighting conditions. Fuji is quite good at low light shots because their chips have the highest usable ISO settings, although I’m not sure if this model uses that chipset. But a photo that’s not taken in good light will show more noise then a photo taken in bright sunlight. I’ve gotten very good 8x10s from a 2MP camera, but you need to have a well lit subject.
Sure, there’ll always be clever schemes for improving prints.
However, the point remains that even these high megapixel cameras are more similar to 35 mm devices than they are to the old 4X5" portrait/landscape/poster cameras.
Even if you won’t do blow-ups, you can do some very serious cropping and keep a decent final resolution. Think of it as an available post-shooting zooming ability. Quality suffers though. You are always better off doing your composition at the time of shooting but still, it is a useful backup plan available.
Intriguing answer, and great facts. I always wondered why there were some 5.0 MP cameras that cost twice as much as the fancy 9 MP ones. My dad asked me what the difference was (I am going to school for Information Technology, and people seem to think if you know some things about computers, you know all that is electronics), and I didn’t really know, other than SLR type cameras were typically better. (not 100% that is true either, but it is what I have heard)
Anyway, if you were comparing two digital cameras, what things would you look for other than MP? Will the salesperson know the size of the pixels?
Also, is there a similar difference between 35mm film cameras? If you wanted to get as good resolution from a digital camera as you would from a mid to upper range 35mm camera, what size pixels and how many would you need?
I’m pretty ignorant of photography, so I have no real sense of comparison between the two. My 3.0 MP camera looks better to me (on screen of course, I never print my pictures), than my dads old 150 dollar camera (the prices were relative to the length of time the cameras were on the market).
I would say that in many cases they outresolve 35mm film. Some of them (like the 16.7 MP Canon EOS-1Ds Mark II) have been shown (although this is somewhat contentious) to be as good as, and perhaps even outresolving, medium format.
I don’t want to get into a holy war about digital v. film, but suffice to say in most shooting conditions, I would prefer to have a digital SLR rather than a 35mm by my side. The only reason I use 35mm anymore these days is for certain moods (like the lovely look of TMax 3200 film or Tri-X) and special effects (shooting with a Lomo).
There’s no clever scheme involved in improving the print. I don’t even use any of those fractal-based upsizing programs. Just Photoshop’s bicubic resampling algorithms. As long as you start with quality information, you can blow up quite large before any sort of deterioration is visible. If you’re viewing from a normal distance, you won’t notice any digital artifacts any more than you would notice obnoxious film grain from a huge 35mm blowup.
1 square inch therefore has 300 * 300 = 90,000 pixels.
We have 9.8 million pixels to play with, so 9,800,000/90,000 = 108.8 square inches.
Take the square root of that, and you have a square 10.4 inches on a side.
One of the biggest myths about digital cameras these days is that more pixels = better. The camera manufacturers have happily responded by making cameras that have totally ridiculous and useless pixel densities. I think some of the other things to look for include image quality (particularly low-light performance), the general ergonomics, the performance of the camera, the quality of the lens used, the amount of manual control - almost anything but MP numbers. And no, the salesperson would most likely not know the size, and would probably dissuade you from asking. I always try to read several reviews of a camera before trying it out in the store to get a more objective picture.
“Good resolution” is a very relative concept. What is the purpose of these pictures? To view on screen, 1024x768 pixels is plenty, but that would be woefully inadequate for a print over postcard size.
The general feeling that I’ve gathered is that high-end SLRs these days match or exceed the resolution of film - but they do need to be matched with good lenses, or that advantage is easily lost.
One more thing. If you want to preserve 2x3 aspect ratio (as you would for 35mm pictures, although digital point & shoots have all sorts of aspect ratios), you would get:
Just take the square root of 9.8 million (about 3,140). That’s the width of a square array that contains 9.8 million pixels. Divide that by the desired resolution, I used 300 dpi, and that’ll give you the width or height of the image. Most cameras use a rectangular rather than a square array, but I’m just ballparking here, and the principle’s the same.
Lord no! My 35mm sits in the closet these days, but I am finding some situations where I have to use bicubic interpolation to get decent grays at a decent print size out of its 8 megapixel replacement.
A good salesperson should know the type and size of the sensor, at least for the most commonly sold models. Of course, you might not find even this level of knowledge if you get your camera at Best Buy. A proper camera store, however, should have staff who know about this stuff.
Dervorin has given some good points about things to look for. Remember, also, that it’s not just about image quality, but about what exactly it is that you want your camera to do for you. If most of your images stay in digital form, and you rarely print anything out, then extremely high quality may not even be very important, because the high-quality output of expensive digital cameras is most noticeable in print.
As i mentioned in an earlier post, i have a Minolta Dimage 7Hi that i bought about four years ago. I like the camera a lot, and it’s served me well, but one thing i really miss is the accurate autofocus that i had with my old autofocus SLR. My Minolta has quite a bit of trouble focusing in low-contrast situations, and you can forget about capturing fast action. If you want to do this sort of thing, then an SLR is virtually essential.
As Dervorin said, low-light performance can be an issue, and is helped dramatically by larger sensors. My camera produces way too much noise (digital variations leading to reduced image quality) if i set the ISO above 200, but newer SLRs can take clean pictures up to ISO1600. This dramatically increases your picture-taking possibilities.
The thing is, there are trade-offs to be made in all these areas, as there usually are when buying electronics. SLRs are better in most cases, but they are also heavier and larger. One reason i traded my old film SLR in for my digital is that the SLR system that i had (two bodies, six lenses) was so large that i hardly ever carried it anywhere. While the digital might have some limitations, it’s small enough that i actually use it. Also, i live in the US and my family is in Australia, so it’s nice to be able to put pictures on the web for them to see.
While a salesperson might, depending on the store, be able to help you through the myriad options you need to consider when selecting a digital camera, i think you can get all the information you need on the web. If you want an excellent, one-stop location for digital camera information, you really can’t go past the Digital Photography Review website. They have in-depth reviews on hundreds of cameras, which include downloadable full-resolution image samples that allow you to compare the actual output of the different cameras. The reviews also have excellent discussion of factors such as ergonomics, controls, ease of use, menus, displays, etc., etc. The full specs for each camera are listed, including things like sensor size, type, etc., so you can compare models.
Even better, DP Review also has an excellent Glossary, which explains in layperson’s language many of the technical terms that are associated with digital photography.
If you’re actually in a lab comparing the output of digital cameras to the output, on high-quality slide film, of film cameras, film still wins the battle in most cases. When Canon released their flagship EOS1Ds Mark II (16 megapixel, full frame 36x24mm sensor), one review i read said that this was the first digital camera they had tested that actually beat the resolution of film in the lab tests. But the Mark II is about $8,000 for the body alone, and isn’t really an option for anyone except professionals and the rich.
In the real world that the rest of us inhabit, whether a digital camera is as good as a film camera really depends on your needs.
If all you ever print out is 6x4 inch glossies for the family album, a decent point-and-shoot will give you picture quality that will be just as good as a regular film camera. This is not to say that the absolute quality of the images is as good, but that you probably won’t notice any differences in a 6x4 print. And, as i said above, if you only look at your pictures on a computer, the difference is even smaller, because computer monitor resolution is only 72 pixels per inch, far below the 300dpi recommended for good prints.
The thing is that many of the tests that photography review sites and magazines do in order to assess a camera’s image quality are almost meaningless for most people’s real world situations. For example, you will see lens reviews that compare the ability of different lenses to resolve fine detail, and these reviews will comment on differences as small as 2 or 3 lines per millimeter (lpm) in the resolving power of the lens. But while such criteria are interesting and important in some ways, the fact is that, unless you’re making massive enlargements, you will never notice such differences. Similarly, in the resolution test i discussed above between the Canon EOS1 Ds and the film cameras, the differences were so small that they needed large magnifiers to see them. The best thing to do is to ask yourself what you need your pictures for, and buy a camera that will do what you need.
Even if you do want better images and more control than is offered by point and shoot cameras, you don’t have to spend a fortune anymore. In most situations below professional level, an entry-level or mid-level digital SLR (Canon EOS 400D, Canon EOS 30D, Nikon D50, Nikon D70/D80) is more than powerful enough for even the most discerning eye, and you can now get a Canon 400D or a Nikon D50 with two lenses for less money than i paid for my Minolta four years ago.
And that’s the key. If it looks good enough to you, and you’re never going to print the pictures anyway, then why worry? Of course, it’s always nice to have something better, and you can get very good digital cameras for reasonable prices now, but ask yourself if a bigger and better camera would be overkill, and if you’ll actually use it. This is an especially important question if you’re thinking making the move to an SLR. They are considerably harder to take to a party or on vacation than a small point-and-shoot camera, and having the best camera in the world won’t help your photography if you leave it behind because it’s too bulky.
You could e-mail me cute pictures of your pet (or kids, vacation, ect) to my work account and fill up my mailbox. And please do not zip them up, no one else does.
To further confuse matters, I have produced 24" by 18" posters by taking 9 pictures so that they fill in a 3x3 grid and using software to turn it into a panorama. The results suffer a bit from a fish eye appearance, but are weirdly sharp. I was using a 5 megapixel camera at the time.
Even if you accept the more-pixels=better idea, having 2x as many pixels only gets you a 1.4x (i.e. square root of 2) improvement. To get 2x better requires 4x the pixel count.
Another point: the larger the image the further away your viewer is likely to be. This means a large print need not be of the same resolution as a smaller one to be considered OK. The rule of thumb is that viewers tend to prefer to be at a distance equal to the diagonal of the print size. This breaks down for very small prints (eyestrain), very large prints in a gallery-like setting and ones of extreme panoramic-like aspect ratio. Useful nonetheless.
